C.2. MySQL Bugzilla Database Introduction
This information comes straight from my life. I was forced to learn how + Bugzilla organizes database because of nitpicky requests from users for tiny + changes in wording, rather than having people re-educate themselves or + figure out how to work our procedures around the tool. It sucks, but it can + and will happen to you, so learn how the schema works and deal with it when it + comes. +
So, here you are with your brand-new installation of Bugzilla. You've got + MySQL set up, Apache working right, Perl DBI and DBD talking to the database + flawlessly. Maybe you've even entered a few test bugs to make sure email's + working; people seem to be notified of new bugs and changes, and you can + enter and edit bugs to your heart's content. Perhaps you've gone through the + trouble of setting up a gateway for people to submit bugs to your database via + email, have had a few people test it, and received rave reviews from your beta + testers. +
What's the next thing you do? Outline a training strategy for your + development team, of course, and bring them up to speed on the new tool you've + labored over for hours. +
Your first training session starts off very well! You have a captive + audience which seems enraptured by the efficiency embodied in this thing called + "Bugzilla". You are caught up describing the nifty features, how people can + save favorite queries in the database, set them up as headers and footers on + their pages, customize their layouts, generate reports, track status with + greater efficiency than ever before, leap tall buildings with a single bound + and rescue Jane from the clutches of Certain Death! +
But Certain Death speaks up -- a tiny voice, from the dark corners of the + conference room. "I have a concern," the voice hisses from the darkness, + "about the use of the word 'verified'. +
The room, previously filled with happy chatter, lapses into reverential + silence as Certain Death (better known as the Vice President of Software + Engineering) continues. "You see, for two years we've used the word 'verified' + to indicate that a developer or quality assurance engineer has confirmed that, + in fact, a bug is valid. I don't want to lose two years of training to a + new software product. You need to change the bug status of 'verified' to + 'approved' as soon as possible. To avoid confusion, of course." +
Oh no! Terror strikes your heart, as you find yourself mumbling "yes, yes, I + don't think that would be a problem," You review the changes with Certain + Death, and continue to jabber on, "no, it's not too big a change. I mean, we + have the source code, right? You know, 'Use the Source, Luke' and all that... + no problem," All the while you quiver inside like a beached jellyfish bubbling, + burbling, and boiling on a hot Jamaican sand dune... +
Thus begins your adventure into the heart of Bugzilla. You've been forced + to learn about non-portable enum() fields, varchar columns, and tinyint + definitions. The Adventure Awaits You! +
C.2.1. Bugzilla Database Basics
If you were like me, at this point you're totally clueless + about the internals of MySQL, and if it weren't for this + executive order from the Vice President you couldn't care less + about the difference between a "bigint" and a + "tinyint" entry in MySQL. I recommend you refer + to the MySQL documentation, available at MySQL.com. Below are the basics you need to know about the Bugzilla database. Check the chart above for more details. +
To connect to your database: +
bash#mysql-u root +
If this works without asking you for a password, + shame on you! You should have + locked your security down like the installation + instructions told you to. You can find details on + locking down your database in the Bugzilla FAQ in this + directory (under "Security"), or more robust security + generalities in the MySQL searchable documentation at + http://www.mysql.com/php/manual.php3?section=Privilege_system . +
You should now be at a prompt that looks like + this:
mysql>
At the prompt, if "bugs" is the name + you chose in thelocalconfig file + for your Bugzilla database, type:
mysqluse bugs;
Don't forget the ";" at the end of + each line, or you'll be kicking yourself later.
C.2.1.1. Bugzilla Database Tables
Imagine your MySQL database as a series of + spreadsheets, and you won't be too far off. If you use this + command:
mysql>show tables from bugs;
you'll be able to see all the + "spreadsheets" (tables) in your database. It + is similar to a file system, only faster and more robust for + certain types of operations.
From the command issued above, ou should have some + output that looks like this: +
+-------------------+ +| Tables in bugs | ++-------------------+ +| attachments | +| bugs | +| bugs_activity | +| cc | +| components | +| dependencies | +| fielddefs | +| groups | +| keyworddefs | +| keywords | +| logincookies | +| longdescs | +| milestones | +| namedqueries | +| products | +| profiles | +| profiles_activity | +| shadowlog | +| tokens | +| versions | +| votes | +| watch | ++-------------------+ + |
+ Here's an overview of what each table does. Most columns in each table have
+descriptive names that make it fairly trivial to figure out their jobs.
+
+attachments: This table stores all attachments to bugs. It tends to be your
+largest table, yet also generally has the fewest entries because file
+attachments are so (relatively) large.
+
+bugs: This is the core of your system. The bugs table stores most of the
+current information about a bug, with the exception of the info stored in the
+other tables.
+
+bugs_activity: This stores information regarding what changes are made to bugs
+when -- a history file.
+
+cc: This tiny table simply stores all the CC information for any bug which has
+any entries in the CC field of the bug. Note that, like most other tables in
+Bugzilla, it does not refer to users by their user names, but by their unique
+userid, stored as a primary key in the profiles table.
+
+components: This stores the programs and components (or products and
+components, in newer Bugzilla parlance) for Bugzilla. Curiously, the "program"
+(product) field is the full name of the product, rather than some other unique
+identifier, like bug_id and user_id are elsewhere in the database.
+
+dependencies: Stores data about those cool dependency trees.
+
+fielddefs: A nifty table that defines other tables. For instance, when you
+submit a form that changes the value of "AssignedTo" this table allows
+translation to the actual field name "assigned_to" for entry into MySQL.
+
+groups: defines bitmasks for groups. A bitmask is a number that can uniquely
+identify group memberships. For instance, say the group that is allowed to
+tweak parameters is assigned a value of "1", the group that is allowed to edit
+users is assigned a "2", and the group that is allowed to create new groups is
+assigned the bitmask of "4". By uniquely combining the group bitmasks (much
+like the chmod command in UNIX,) you can identify a user is allowed to tweak
+parameters and create groups, but not edit users, by giving him a bitmask of
+"5", or a user allowed to edit users and create groups, but not tweak
+parameters, by giving him a bitmask of "6" Simple, huh?
+ If this makes no sense to you, try this at the mysql prompt:
+mysql> select * from groups;
+ You'll see the list, it makes much more sense that way.
+
+keyworddefs: Definitions of keywords to be used
+
+keywords: Unlike what you'd think, this table holds which keywords are
+associated with which bug id's.
+
+logincookies: This stores every login cookie ever assigned to you for every
+machine you've ever logged into Bugzilla from. Curiously, it never does any
+housecleaning -- I see cookies in this file I've not used for months. However,
+since Bugzilla never expires your cookie (for convenience' sake), it makes
+sense.
+
+longdescs: The meat of bugzilla -- here is where all user comments are stored!
+You've only got 2^24 bytes per comment (it's a mediumtext field), so speak
+sparingly -- that's only the amount of space the Old Testament from the Bible
+would take (uncompressed, 16 megabytes). Each comment is keyed to the
+bug_id to which it's attached, so the order is necessarily chronological, for
+comments are played back in the order in which they are received.
+
+milestones: Interesting that milestones are associated with a specific product
+in this table, but Bugzilla does not yet support differing milestones by
+product through the standard configuration interfaces.
+
+namedqueries: This is where everybody stores their "custom queries". Very
+cool feature; it beats the tar out of having to bookmark each cool query you
+construct.
+
+products: What products you have, whether new bug entries are allowed for the
+product, what milestone you're working toward on that product, votes, etc. It
+will be nice when the components table supports these same features, so you
+could close a particular component for bug entry without having to close an
+entire product...
+
+profiles: Ahh, so you were wondering where your precious user information was
+stored? Here it is! With the passwords in plain text for all to see! (but
+sshh... don't tell your users!)
+
+profiles_activity: Need to know who did what when to who's profile? This'll
+tell you, it's a pretty complete history.
+
+shadowlog: I could be mistaken here, but I believe this table tells you when
+your shadow database is updated and what commands were used to update it. We
+don't use a shadow database at our site yet, so it's pretty empty for us.
+
+versions: Version information for every product
+
+votes: Who voted for what when
+
+watch: Who (according to userid) is watching who's bugs (according to their
+userid).
+
+
+===
+THE DETAILS
+===
+
+ Ahh, so you're wondering just what to do with the information above? At the
+mysql prompt, you can view any information about the columns in a table with
+this command (where "table" is the name of the table you wish to view):
+
+mysql> show columns from table;
+
+ You can also view all the data in a table with this command:
+
+mysql> select * from table;
+
+ -- note: this is a very bad idea to do on, for instance, the "bugs" table if
+you have 50,000 bugs. You'll be sitting there a while until you ctrl-c or
+50,000 bugs play across your screen.
+
+ You can limit the display from above a little with the command, where
+"column" is the name of the column for which you wish to restrict information:
+
+mysql> select * from table where (column = "some info");
+
+ -- or the reverse of this
+
+mysql> select * from table where (column != "some info");
+
+ Let's take our example from the introduction, and assume you need to change
+the word "verified" to "approved" in the resolution field. We know from the
+above information that the resolution is likely to be stored in the "bugs"
+table. Note we'll need to change a little perl code as well as this database
+change, but I won't plunge into that in this document. Let's verify the
+information is stored in the "bugs" table:
+
+mysql> show columns from bugs
+
+ (exceedingly long output truncated here)
+| bug_status| enum('UNCONFIRMED','NEW','ASSIGNED','REOPENED','RESOLVED','VERIFIED','CLOSED')||MUL | UNCONFIRMED||
+
+ Sorry about that long line. We see from this that the "bug status" column is
+an "enum field", which is a MySQL peculiarity where a string type field can
+only have certain types of entries. While I think this is very cool, it's not
+standard SQL. Anyway, we need to add the possible enum field entry
+'APPROVED' by altering the "bugs" table.
+
+mysql> ALTER table bugs CHANGE bug_status bug_status
+ -> enum("UNCONFIRMED", "NEW", "ASSIGNED", "REOPENED", "RESOLVED",
+ -> "VERIFIED", "APPROVED", "CLOSED") not null;
+
+ (note we can take three lines or more -- whatever you put in before the
+semicolon is evaluated as a single expression)
+
+Now if you do this:
+
+mysql> show columns from bugs;
+
+ you'll see that the bug_status field has an extra "APPROVED" enum that's
+available! Cool thing, too, is that this is reflected on your query page as
+well -- you can query by the new status. But how's it fit into the existing
+scheme of things?
+ Looks like you need to go back and look for instances of the word "verified"
+in the perl code for Bugzilla -- wherever you find "verified", change it to
+"approved" and you're in business (make sure that's a case-insensitive search).
+Although you can query by the enum field, you can't give something a status
+of "APPROVED" until you make the perl changes. Note that this change I
+mentioned can also be done by editing checksetup.pl, which automates a lot of
+this. But you need to know this stuff anyway, right?
+
+ I hope this database tutorial has been useful for you. If you have comments
+to add, questions, concerns, etc. please direct them to
+mbarnson@excitehome.net. Please direct flames to /dev/null :) Have a nice
+day!
+
+
+
+===
+LINKS
+===
+
+Great MySQL tutorial site:
+http://www.devshed.com/Server_Side/MySQL/
+
+